【作者】 高磊；

【导师】 孙德军；

【作者基本信息】 山东大学 ， 胶体与界面化学， 2010， 硕士

【摘要】 随着国内外石油工业的发展和对石油需求的不断增长,油田勘探开发逐渐从浅部地层向深部地层、由浅海向深海转变,对钻井液提出了更高的抗温和抗盐要求。本文拟通过提高处理剂自身耐温耐盐性能来加强水基钻井液高温稳定性,采用分子结构设计理论,优选出四种不同的单体：2-丙烯酰胺基-2-甲基丙磺酸(AMPS)、丙烯酰胺(AM)、N,N-二甲基丙烯酰胺(DMAM)、N-乙烯吡咯烷酮(NVP),利用自由基水溶液聚合法合成了P(AMPS-AM-DMAM-NVP)四元共聚物作为高温水基钻井液降滤失剂,有效地提高了水基钻井液耐温耐盐性能。一、P(AMPS-AM-DMAM-NVP)四元共聚物的合成与表征P(AMPS-AM-DMAM-NVP)四元共聚物的自由基水溶液聚合实验采用正交实验法和改变单体浓度法得到了最佳反应条件：引发剂过硫酸钾(KPS)用量0.3wt%(占单体质量分数),单体摩尔比AMPS:AM:DMAM:NVP=3:4:2:1,络合剂乙二胺四乙酸(EDTA)用量0.15wt%(占单体质量分数),温度75℃,单体浓度30wt%(质量分数),反应时间6 h。红外光谱分析验证了四元共聚物中各单体的存在以及反应的完全性；元素分析实验基本证明了合成聚合物与设计聚合物组成一致；特性粘度实验确定了四元共聚物的粘均分子量约为72.23万；热重-差示扫描量热(TG-DSC)实验和特性粘度保留率实验表明合成共聚物具有良好的耐温性。二、P(AMPS-AM-DMAM-NVP)四元共聚物在不同泥浆体系中的降滤失效果评价通过流变和滤失实验,发现共聚物浓度、温度、NaCl浓度、老化时间等对泥浆体系流变和滤失性质具有重要的影响。共聚物的加入使得淡水泥浆、盐水泥浆、复合盐水泥浆和饱和盐水泥浆在高温老化后具有不增粘以及良好的降滤失效果。与国外产品Driscal D相比发现,高温老化后,在淡水泥浆、复合盐水泥浆中两者降滤失效果相当；在盐水泥浆、饱和盐水泥浆中,共聚物降滤失效果优于Driscal D。这表明此共聚物有望在深井钻探中得到应用。三、P(AMPS-AM-DMAM-NVP)四元共聚物与蒙脱土的相互作用研究为了更好的解释共聚物在粘土分散体系中的耐温耐盐性,利用总有机碳分析实验和流变实验研究了共聚物与蒙脱土的相互作用。结果发现：随着共聚物浓度增加,其在蒙脱土颗粒表面的吸附量增加并逐渐达到吸附平台,符合Langmuir型吸附等温线；电解质的加入使共聚物在钠蒙脱土颗粒表面吸附量增加,在较低浓度下,CaCl2对共聚物在颗粒表面吸附的影响程度大于NaCl；继续增加电解质浓度,随CaCl2浓度增加出现饱和吸附平台,而随NaCl浓度增加并未出现饱和吸附的趋势；温度增加,共聚物在颗粒表面吸附量降低。流变实验结果表明,共聚物水溶液符合幂律模型,随浓度增加,流型曲线上升；随剪切速率增加,粘度降低,具有剪切稀释性；而钠蒙脱土分散体系及共聚物-钠蒙脱土复合体系均符合Herschel-Bulkely模型,随着共聚物浓度增加,屈服值和稠度系数随之增加而流型指数减小,这与振荡频率扫描实验结果一致；无论是钠蒙脱土分散体系还是共聚物-钠蒙脱土复合体系,随着NaCl浓度的增加,体系屈服值和稠度系数均表现出先增大后减小的趋势,流型指数正好相反。四、P(AMPS-AM-DMAM-NVP)四元共聚物降滤失机理研究从胶体与界面化学的基本理论出发,初步提出了共聚物的降滤失机理,可以概括为：(1)利用共聚物在颗粒表面吸附提高静电排斥力、疏水作用力、水化膜斥力来稳定粘土颗粒；(2)共聚物对粘土分散体系起增粘作用,降低了滤液的流动性,增加了渗滤阻力；(3)共聚物的加入有助于粘土分散体系中结构网的形成,提高聚结稳定性；(4)共聚物本身的分子尺寸在胶体颗粒范围之内,它的加入相当于增加了胶体颗粒的含量,对滤饼起到封堵孔隙的作用。更多还原

【Abstract】 With the development of oil industry at home and abroad and the ever-increasing demand for oil, the exploitation and development of oilfield was shifted from shallow strata to deep strata and from shallow sea to deep sea, which has made a claim for higher temperature and higher salt concentrations in drilling fluid. Polymer with improved high temperature resistance and salt tolerance was collected as additive to enhance the high temperature stability of water-base drilling fluid. According to the theories of molecular structure design, four different monomers were optimized as follows:2-acrylamido-2-methyl-propane sulfonic acid (AMPS), acrylamide(AM), N,N-dimethyl acrylamide (DMAM) and N-vinylpyrrolidone (NVP). Quadripolymer as high temperature fluid loss reducer was synthesized by adopting free radical water solution polymerization method, which effectively improved the performance of water-base drilling fluid with high temperature resistance and salt tolerance.1. Preparation and characterization of P(AMPS-AM-DMAM-NVP) quadripolymerThe optimum conditions of synthesis were determined through orthogonally designed experiments and altering monomer concentration methods as follows:the initiator potassium persulfate (KPS) dosage 0.3 wt% (of monomer concentration), the monomer molar ratio AMPS:AM:DMAM:NVP=3:4:2:1, the chelator ethylene diamine tetraacetic acid (EDTA) dosage 0.15 wt% (of monomer concentration), the reaction temperature 75℃, the monomer concentration 30 wt% and the reaction time 6h. The Fourier transform infrared (FTIR) spectroanalysis revealed the presence of four monomers and confirmed the effectiveness of the reaction. The Element analysis showed the composition of synthetic polymer was in accord with designed polymer. The average viscosimetric molecular weight of quadripolymer was obtained by the intrinsic viscosity method, which was 72.23x 104. Both thermogravimetric-differential scanning calorimetry (TG-DSC) method and the retainable ratio of intrinsic viscosity showed the synthetic polymer had good high temperature resistance property.2. Evaluation of filtration control properties about P(AMPS-AM-DMAM-NVP) quadripolymer at different mud The results of rheological and filtration experiments showed quadripolymer concentrarions, temperature, NaCl concentrations and aging time had an important effect on the rheological and filtration properties of mud. Fresh water mud, salt water mud, compound salt water mud and saturated saline-water mud didn’t increase viscosity and had good filtration properties after high temperature aging with the addition of quadripolymer. For fresh water mud and compound salt mud, the quadripolymer had same performance in controlling the filtration compared with the Driscal D. For salt water mud and saturated saline-water mud, it had better performance in controlling the filtration compared with the Driscal D. This shows that quadripolymer can be expected to be applied in deep drilling.3. Research on the interaction of P(AMPS-AM-DMAM-NVP) quadripolymer with montmorilloniteIn order to explain better the high temperature resistance and salt tolerance of quadripolymer in clay dispersion, the total organic carbon analysis experiments(TOC) and rheological experiments were used to research the interaction of quadripolymer with montmorillonite. The results showed the adsorbance increased with increasing quadripolymer concentration until a plateau region presented, which confirmed Langmuir adsorption isotherms. The addition of electrolytes made the adsorbance of quadripolymer in the surface of particles increase. At lower concentrations, the effect of CaCl2 were more significant than NaCl. Saturated adsorption platform appeared with the increase of CaCl2 concentration, while the adsorbance continued to increase with the increasing NaCl concentration without the tendency of saturated adsorption.The results of rheological experiments revealed that the flow curves of quadripolymer solution could be well described by the power law model. The flow curves raised with increasing quadripolymer concentration. The viscosity decreased with increasing shear rate, which exhibited the shear shinning properties. For montmorillonite dispersion and quadripolymer-montmorillonite dispersions, flow curves could be discribed by the Herschel-Bulkely model. With the increase of quadripolymer concentrations, yield value and consistency coefficient increased and flow indices decreased, which was confirmed with the oscillatory frequency scan measurements. With the addition of NaCl, yield value and consistency coefficient increased firstly and then decreased, while flow indices had the opposite tendency.4. Research on mechanisms of P(AMPS-AM-DMAM-NVP) quadripolymer in controlling filtrationAccording to theory of Colloid and Interface Chemistry, some mechanisms of quadripolymer in controlling filtration were initially proposed. It can be summarized as follows:(1) Electrostatic repulsive force, hydrophobic interaction and hydration repulsion force between particles were enhanced by using the adsorption of polymer in the particle surface, which stabilized the clay particles; (2) The viscosity of mud increased with the addition of polymer, which reduced the liquidity of filtrate and increased the resistance of percolation; (3) The network structure of clay system was formed with the addition of polymer, which improved coagulation stability of clay system. (4) The molecular size of polymer was within the scope of the colloidal particles. Hence, the addition of polymer was equivalent to increasing the content of colloid particles, which had an effect on plugging the pores of the filter cake.更多还原